Hi: I will be hiking on the PCT this summer during Aug/Sept. I will cover Crater Lake to Canada. I know it can rain a bit there. Question: Would carrying the one pound Kimtah rain jacket be overkill? I do usually use Dri Ducks, but worry a bit about the rain on the spine of the Cascades.

I've been in a LOT of rain over 5,000 or so miles of backpacking trips. Washington brought rain that surprised even this hardened New Englander. I bought a rain jacket in Oregon for the Washington section of my PCT thru-hike last year, and it wetted out within 3 hrs of the constant / all-day downpours. Bring your 1 lb Kimtah and be happy with it ! Hypothermia is a real concern in prolonged WA rain.

You might also consider a lightweight yet sturdy umbrella like the GoLite Chrome Dome (8oz, $25). This has the much added benefit of being quite useful rain or shine, unlike most rain jackets (i.e. it provides nice shade from the sun and keeps you cooler).

I know some people have paired a very light rain jacket (like the DriDucks variety) with a Chrome Dome to deal with lots of rain. Usually the jacket is left unzipped and mainly acts to cover the arms from errant spray. I usually just pair a windshell with my own Chrome Dome to deal with the misty rain here in the PNW on my walks home from work, but I've used a Marmot Super Mica WPB jacket as well (unzipped) to great effect.

I have no experience hiking on the PCT in Washington during September, so I can't comment on the conditions you'll face there, but you will certainly not need your heavy rain jacket for August in Oregon (I live here, August is quite dry).

I would say your choice ultimately depends on the rest of your kit and how it all works together … evaluating and understanding how your gear works in the aggregate is the crux of being smart and safe when making decisions with a UL gear-list … but that said I finished in 2012 around September 15th and had only one day of light rain in all of Oregon and Washington combined.

Sounds like two really different environments. Perhaps switch to heavy 1# rain coat up the trail in WA where it seems to be needed in the cold rain. I do have a chrome dome and usually carry it on the AT for walking in the warm rain.

I've lived and hiked in OR and WA for 28 years. Your Dry Ducks and umbrella will be fine for OR in August. I'd change to my full-on rain parka and rain pants (lots of wet brush) at either Cascade Locks or Snoqualmie Pass. If I wanted to push my luck, I'd do it at Stevens Pass. There's no way I'd go north of Stevens Pass in mid to late August without full-on rain jacket and pants. My insulating layer is always synthetic in the North Cascades.

September rains in the North Cascades can be vicious beasts. Multi-day continuous rains of varying intensities are common. Snow is not unheard of although it rarely stays. These are usually driven by pretty solid wind and with temperatures in the 40° to 50° F range. Read in "ideal hypothermia weather".

From Snoqualmie Pass north, the terrain gets steadily steeper, higher, and has fewer potential bail-out points. While rarely above treeline, it can be a nasty place to get caught in a storm.

Example: In early September, I was northbound, approaching Harts Pass from the south, and looked back to see storm clouds and rain coming up the small canyon behind me. Rather than camp at the bottom of that canyon, I elected to keep going (albeit at a faster pace) up the north side. I misjudged the speed of the storm's advance. It caught me about half-way up. Fortunately, there was a large treed bench there where I hastily set up camp. The rain poured and temperatures dropped.

The next morning, in full Gortex parka and rain pants, I continued north towards Harts Pass, expecting the storm to be short-lived. The wind-driven rain and cold temperatures meant that even hiking up-hill and wearing my fleece under my parka, I could not get warm. It turned out that a local was heading south at the same time and had also been forced to camp on the same bench, less than 100 yards from me. Neither of us saw the other due to the rain. He – and most of the local hunters – had seen this stuff before, knew what it portended, and turned back to Harts Pass to go home. I caught up to him at the pass, and he offered me a ride into Winthrop, 18 miles away. I wisely took it. There's no public transportation in that area so my wife drove 6 hours from Portland to rescue me.

This turned out to be a very strong storm. It poured steadily for 5 days up in the North Cascades. I returned the following year to complete the 35 miles to Manning Park.